mcs/class/corlib/System.IO/TextReader.cs

   1 //\r
   2 // System.IO.TextReader\r
   3 //\r
   4 // Authors:\r
   5 //   Marcin Szczepanski (marcins@zipworld.com.au)\r
   6 //   Miguel de Icaza (miguel@gnome.org)\r
   7 //\r
   8 \r
   9 using System;\r
  10 using System.Runtime.InteropServices;\r
  11 \r
  12 namespace System.IO {\r
  13 \r
  14         [Serializable]\r
  15         public abstract class TextReader : MarshalByRefObject, IDisposable {\r
  16                 \r
  17                 protected TextReader() { }\r
  18                 \r
  19                 public static readonly TextReader Null;\r
  20                 \r
  21                 public virtual void Close()\r
  22                 { \r
  23                         Dispose(true);\r
  24                 }\r
  25 \r
  26                 void System.IDisposable.Dispose()\r
  27                 {\r
  28                         Dispose(true);\r
  29                 }\r
  30 \r
  31                 protected virtual void Dispose( bool disposing )\r
  32                 {\r
  33                         return;\r
  34                 }\r
  35                 \r
  36                 public virtual int Peek()\r
  37                 {\r
  38                         return -1;\r
  39                 }\r
  40                 \r
  41                 public virtual int Read()\r
  42                 {\r
  43                         return -1;\r
  44                 }\r
  45                 \r
  46
  47                 public virtual int Read ([In, Out] char[] buffer, int index, int count)\r
  48                 {\r
  49                         int c, i;\r
  50                         \r
  51                         for (i = 0; i < count; i++) {\r
  52                                 if ((c = Read ()) == -1)\r
  53                                         return i;\r
  54                                 buffer [index + i] = (char)c;\r
  55                         }\r
  56                         \r
  57                         return i;\r
  58                 }\r
  59                 \r
  60                 public virtual int ReadBlock ([In, Out] char [] buffer, int index, int count)\r
  61                 {\r
  62                         int total_read_count = 0;\r
  63                         int current_read_count = 0;\r
  64 \r
  65                         do {\r
  66                                 current_read_count = Read (buffer, index, count);\r
  67                                 index += current_read_count;\r
  68                                 total_read_count += current_read_count;\r
  69                                 count -= current_read_count;\r
  70                         } while (current_read_count != 0 && count > 0);\r
  71 \r
  72                         return total_read_count;\r
  73                 }\r
  74 \r
  75                 public virtual string ReadLine()\r
  76                 { \r
  77                         return String.Empty;\r
  78                 }\r
  79 \r
  80                 public virtual string ReadToEnd()\r
  81                 { \r
  82                         return String.Empty;\r
  83                 }\r
  84 \r
  85                 public static TextReader Synchronized (TextReader reader)\r
  86                 {\r
  87                         if (reader == null)\r
  88                                 throw new ArgumentNullException ("reader is null");\r
  89                         if (reader is SynchronizedReader)\r
  90                                 return reader;\r
  91 \r
  92                         return new SynchronizedReader (reader);\r
  93                 }       \r
  94         }\r
  95 \r
  96         //\r
  97         // Synchronized Reader implementation, used internally.\r
  98         //\r
  99         [Serializable]\r
 100         internal class SynchronizedReader : TextReader {\r
 101                 TextReader reader;\r
 102                 \r
 103                 public SynchronizedReader (TextReader reader)\r
 104                 {\r
 105                         this.reader = reader;\r
 106                 }\r
 107 \r
 108                 public override void Close ()\r
 109                 {\r
 110                         lock (this){\r
 111                                 reader.Close ();\r
 112                         }\r
 113                 }\r
 114 \r
 115                 public override int Peek ()\r
 116                 {\r
 117                         lock (this){\r
 118                                 return reader.Peek ();\r
 119                         }\r
 120                 }\r
 121 \r
 122                 public override int ReadBlock (char [] buffer, int index, int count)\r
 123                 {\r
 124                         lock (this){\r
 125                                 return reader.ReadBlock (buffer, index, count);\r
 126                         }\r
 127                 }\r
 128 \r
 129                 public override string ReadLine ()\r
 130                 {\r
 131                         lock (this){\r
 132                                 return reader.ReadLine ();\r
 133                         }\r
 134                 }\r
 135 \r
 136                 public override string ReadToEnd ()\r
 137                 {\r
 138                         lock (this){\r
 139                                 return reader.ReadToEnd ();\r
 140                         }\r
 141                 }\r
 142 #region Read Methods\r
 143                 public override int Read ()\r
 144                 {\r
 145                         lock (this){\r
 146                                 return reader.Read ();\r
 147                         }\r
 148                 }\r
 149 \r
 150                 public override int Read (char [] buffer, int index, int count)\r
 151                 {\r
 152                         lock (this){\r
 153                                 return reader.Read (buffer, index, count);\r
 154                         }\r
 155                 }\r
 156 #endregion\r
 157                 \r
 158         }\r
 159 }\r